The function of electrical switchgear such as circuit breakers is to decouple a number of power-consuming loads from a voltage supply network if a specific malfunction occurs. The classic malfunction is the occurrence of a short-circuit current, and traditionally the circuit breakers are designed to move a switching element in the event of such a short-circuit current and thereby decouple the connection between loads and network.
Electrical switchgear is usually installed in switchgear cabinets in order to provide protection therefor. Typically such a switchgear cabinet is arranged in the vicinity of a machine which is controlled by the electronic equipment housed inside the switchgear cabinet. In order to prevent unauthorized third parties from gaining access the electrical switchgear it is known to embody the switchgear cabinet doors as lockable. For activation and deactivation purposes the electrical switchgears are equipped with drives. In other words, the drives are arranged on the electrical switchgears and enable the electrical switchgears to be switched on and off. In this case use is made in particular of drives which are movable between a switch-on position and a switch-off position in order to activate or deactivate an electrical switchgear.
Examples of known drives include direct drives, door coupling rotary drives, sidewall rotary drives and motor drives. Mechanical door locking devices for rotary drives for electrical switchgear, such as low-voltage switchgear, are known for the purpose of protecting people. In this case the mechanical door locking device in direct drives, as an integral part of the direct drive, is released as part of the electrical switchgear. In door coupling rotary drives the mechanical door locking device is released as an integral part of the coupling element between shaft and operating handle. No mechanical door locking device is known in the case of sidewall rotary drives.
When electrical switchgears are in an energized state the switchgear cabinet door should be locked for safety reasons so that an operator cannot come into contact with live parts. Furthermore, the lock should ensure that the electrical switchgear can only be activated when the switchgear cabinet door is closed.
In prior art solutions switchgear cabinet doors are locked by way of door coupling rotary drives, expanded direct drives or direct drives. In order for said drives to be able to lock the switchgear cabinet door they must be mounted directly on or behind the switchgear cabinet door. So-called remote door locking devices can be used in the case of a remote arrangement of electrical switchgear and/or drive of the electrical switchgear and switchgear cabinet door. A problem in this situation is that prior art remote door locking devices cannot detect whether the switchgear cabinet door is open or closed.